In general, a refrigerator is a device for keeping storage items such as food, beverage, and the like, in storage for a long period of time, and refrigerating or freezing storage items according to their types desired to be kept in storage.
The refrigerator operates according to driving of a compressor provided therein. Cooling air provided to the interior of the refrigerator is generated according to a heat exchange operation of a refrigerant and continuously provided to the interior of the refrigerator according to a repeated cycling operation of compression-condensation-expansion-evaporation. The provided refrigerant is evenly transferred to the interior of the refrigerator according to a convection current to allow the food items within the refrigerator to be kept at a desired temperature.
Recently, consumers demand for refrigerators that may provide a great utilization efficiency of the storage space capable of storing various storage items that change according to the elevation of the standard of living, as well as the conventional cooling efficiency, is increasing. Also, demand for various additional functions improving user convenience is increasing. For example, users are becoming interested in a robot refrigerator including a robot technique. Namely, users who want to use a refrigerator show an interest in the technique of moving and using a refrigerator by using a remote controller.